import { useState, useEffect } from "react";
import { addons } from "storybook/preview-api";
import { DARK_MODE_EVENT_NAME } from "./constants";
import { store } from "./store";

/**
 * Returns the current state of storybook's dark-mode
 */
export function useDarkMode(): boolean {
  const [isDark, setIsDark] = useState(() => store().current === "dark");

  useEffect(() => {
    const chan = addons.getChannel();

    chan.on(DARK_MODE_EVENT_NAME, setIsDark);

    return () => chan.off(DARK_MODE_EVENT_NAME, setIsDark);
  }, []);

  return isDark;
}

export * from "./constants";